ArcHydro Problem Solvers

This is a collection of actions I've learned to take when I'm having problems with ArcHydro or HEC-GeoHMS. I'll add to the list when I find more.

Make sure the Geoprocessing extents include the whole project: Go to the Geoprocessing menu>Environments...>Processing Extent. Under Processing Extent choose a layer that you know covers the full extent of the waters you are processing and click OK. This should ensure that the processing extent is large enough to do what you want.

Delete everything you can in your temp folder: Mine is C:\Users\mboucher\AppData\Local\Temp. Get out of ArcMap first to clear temp files related to your project. You can do this without getting out of ArcMap through the ArcHydro Toolbar under ApUtilities>Additional Utilities>Clean User's Temp Folder.

Make sure your Target Locations are correct: Under ApUtilities>Set Target Locations, make sure the HydroConfig and they GeoHMSConfig Targets make sense. The raster data should go to the project folder vector data to a geodatabase. The raster data will go to a folder in the project folder with the dataframe name and the vector data to a feature data set with the dataframe name. Through the ArcHydro Toolbar under there is a function to reset the target locations: ApUtilities>Additional Utilities>Reset Target Locations. I've not tested this to see if it corrects everything.

When working on a complicated model, don't use the model mxd for your presentation map. It just adds baggage to an already "heavy" mxd.

If you have additional actions or clarifications on these, please chime in.

I've started a practice that seems to make many errors/crashes go away.

Layers/rasters needed for Arc Hydro are:

DEM PROCESSING:

rawdem (Extracted by mask from county-wide dem for each project. Set processing extents using this or mask ploly)

agreestream*

innerwalls*

outerwalls*

*I do work all over my County and so have county-wide "master" geodatabase for these that I use on all my Arc Hydro Projects.

WATERSHED DELINEATION:

BatchPoints

If I have these layers, I can recreate the hydrologically correct DEM (HC DEM) anytime I want and re-delineate the watersheds.

So my practice is this: As I'm developing my HC DEM, and have to modify the agreedem, innerwalls, outerwalls layers, I can save the BatchPoints to my project folder and then delete the geodatabase and folder with rasters in it (Target Locations). This starts everything fresh and new. Then I can use model builder to reprocess the watersheds. When I'm ready to re-delineate the watersheds, I copy the BatchPoints into the geodatabase and set the BatchDone value to "0".

I run the watershed delineation, etc. via the Arc Hydro menus though I could possibly do this via Model Builder also. Since I've started doing this (and following solutions in the postings above on this thread), my crashes and errors have all gone away! Here is the ModelBuilder model for my latest project. I don't use outerwalls on this project, but that could be added.

As an addition to the earlier tips. I just found that when I put the mxd in a folder with a simple name and no spaces, the Terrain Processing with Arc Hydro ran without a hitch.

Today I happened to look in the "log" file in the raster folder for the project and saw that a raster name was cut off. In the example below you can see that the flow accumluation file name was cut off after the "f".

You can see that their is much more to the file name and some other info. I don't know if there is a limit to the length of the path or if some functions don't like the spaces in the path. Eitherway, I'm going to keep things short and spaceless for a while and see if that works. I've been aware of naming problems when there were spaces, but that hasn't seemed to cause a problem before. I've always muscled through it.

With this change in practice, I used the canned terrain processing model with no problems.

One more thing... I've gathered from other posts that when using GeoHMS, things work better if you turn off background processing. Go to Geoprocessing>Geoprocessing Options... and uncheck "Enable" under "Background Processing".

I recently had a problem using the Stream Definition tool while delineating catchments. This problem started out of the blue, and I'd been using the same process I've used repeatedly in the past (with success).

I followed all of the recommended actions (clear temp folder, set target locations, new mxd, restart the computer, even updated to version 10.3.0.6), but was still getting the following error when running Stream Definition:

Failed to execute. Parameters are not valid.

ERROR 000860: Input true raster or constant value: is not the type of Composite Geodataset, or does not exist.

Failed to execute (Con).

Failed at Tue Apr 14 09:16:34 2015 (Elapsed Time: 0.02 seconds)

System.Runtime.InteropServices.COMException (0x80004005): Error HRESULT E_FAIL has been returned from a call to a COM component.

I turned background geoprocessing ON, and the Stream Definition tool worked correctly. HOWEVER, this worked with a FAC grid that was created with background geoprocessing OFF. I tried the process from the beginning with BGGP OFF, and the resulting FDR grid contained more than the normal 9 values.

At least for me, it seems I need to turn BGGP OFF in general, and turn it ON when running Stream Definition. Also unsure why this problem started out of the blue, but wanted to put the information out there in case anyone else is having the same issues.

I've started a practice that seems to make many errors/crashes go away.

Layers/rasters needed for Arc Hydro are:

DEM PROCESSING:

rawdem (Extracted by mask from county-wide dem for each project. Set processing extents using this or mask ploly)

agreestream*

innerwalls*

outerwalls*

*I do work all over my County and so have county-wide "master" geodatabase for these that I use on all my Arc Hydro Projects.

WATERSHED DELINEATION:

BatchPoints

If I have these layers, I can recreate the hydrologically correct DEM (HC DEM) anytime I want and re-delineate the watersheds.

So my practice is this: As I'm developing my HC DEM, and have to modify the agreedem, innerwalls, outerwalls layers, I can save the BatchPoints to my project folder and then delete the geodatabase and folder with rasters in it (Target Locations). This starts everything fresh and new. Then I can use model builder to reprocess the watersheds. When I'm ready to re-delineate the watersheds, I copy the BatchPoints into the geodatabase and set the BatchDone value to "0".

I run the watershed delineation, etc. via the Arc Hydro menus though I could possibly do this via Model Builder also. Since I've started doing this (and following solutions in the postings above on this thread), my crashes and errors have all gone away! Here is the ModelBuilder model for my latest project. I don't use outerwalls on this project, but that could be added.

Dear Mark,my thanks for reply.The matter is that befor I applyed the Forum I have read information there and deleleted all files from directory by using "Clean Usre's Temp Folder". But these actions didn't help. I simply don't know what to do.Now I again clean this folder , but have got the same negative result.Please, advise me what I have to do more.Besty regardsYury

However, I have to disagree with the flow chart in this link (part of the same series). I would always perform a fill before running the flow direction. There is something wrong with the flow chart. It should show the process going from the dimensionless DEM box to a flow direction step then to the flow accumulation. Sorry, I'm being a little picky here, but someone new to this could get frustrated by the flowchart. The steps I use are posted and/or linked elsewhere in this thread (see post #2 in the post right before this one). http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Deriving_runoff_characteristics/009z0000005p000000/.

Even after making the adjustments recommended in this thread, I would say 50% of the time I get an error message similar to the one seen in the top link. The other half of the time, I get a Flow Direction raster that has no attributes. Any ideas what the heck is going on or how to rectify this situation?

I've been meaning to make a list of things to do before starting an Arc Hydro project. JAdams15's question pushed me to do it. This is more to remind myself and staff here that might venture into watershed processing than anything else. I hate making the same mistakes twice. Many of these ideas you'll find earlier in this thread.

Getting a project started:

For fastest processing, put the project directory on your local computer (C: drive). Processing over a network kills your speed.

Keep the layer, file, and directory names short and with no spaces or non-alpha numeric characters. Use "_" if you must. I don't use "-". I suspect it causes problems.

Make sure the HydroConfig Target Locations are correct. If you start the project and then move it to another folder, the Target Locations will not change on their own. The GeoHMSConfig Target Locations should be checked if using GeoHMS. Use the ApUtilities > Additional Utilities>Reset Target Locations menu command to reset them. I always check them under ApUtilities>Set Target Locations.

Make sure the Spatial Analyst extension is selected under Customize>Extensions.

Make sure your Geoprocessing Extents match the area you want to process. Use Geoprocessing>Environments>Processing Extent menu command. I make it match the DEM or the mask I used to extract the DEM for the project. In doing batch point delineation I've had this change to the batch point extent and produce puzzling results.

Disable Background Processing via Geoprocessing>Options menu.

Set the "Max number of unique values to render" to a high number (I use 30,000,000: Don't ask me why.) Adjust this setting under Customize>ArcMap Options>Raster tab>Raster Dataset tab.

Putting the agreestream, innerwall and outerwall layers in a geodatabase is a good idea.

After you've been working on the project a while:

If you are starting over on the process after getting much of the way through it, close Arc Map and via Windows Explorer delete the folders (would have the same name as your data frame) and the geodatabase (would have the same name as your mxd). This makes sure there are not locks on layers/rasters and no denials for overwriting files. The only layer I copy out of this is the Batch Point layer. I make a copy in the main directory so I don't have to create them again.

Clear out the temp file directory. Do this as often as you think of it. There's a tool under ApUtilities that does this nicely.

At times, a reboot of the PC does wonders. I'm not sure why this helps other than it might eliminate software conflicts if you are using more than one program.

I placed my data (GRID named testdem) to C:\work\ and set targets to C:\work\ (raster) and C:\work\testing.gdb (vector)I also set processing extent to the extent of testdem, disabled background processing threw some salt over my shoulder and yet I got this error. After that I moved my testing.mxd to the same folder I was able to ran the sink evaluation tool with success. How ever the same tool still fails when using Basic terrain processing...

# SOLUTION #1. I also needed to change the default workspace from C:\ESRI\...\default.gdb to C:\work\testing.gdb.2. I also changed my dataframe name to "data" to avoid any conflicts (see below).

I was wondering why the default paths keep having my data frame name in the paths? i.e. the vector outputs by default are going to C:\work\testing.gdb\MY DATA FRAME NAME\OutPutFile

A problem I have encountered is that some vector files are being processed without necessary fields. The DrainageLine file needs a field labeled "DrainID" for AdjointCatchment to process. If it does not have the field, just add it and set it equal to "GridID."

A problem I have encountered is that some vector files are being processed without necessary fields. The DrainageLine file needs a field labeled "DrainID" for AdjointCatchment to process. If it does not have the field, just add it and set it equal to "GridID."

I have not encountered this, or at least I have not looked at the fields after a process has failed to see if anything is missing. Possibly the missing fields are the cause of the crashes. The crashes, I've found are nearly eliminated when working on my local computer and not over the network. Maybe, when working over the network, the slow processing causes a "hiccup" in the processing steps and the fields are not created thereby causing the crash.

I am no network guru, but I am familiar with radio data communications. In our radio based data collection system (SCADA) there is a "time out" setting. If one radio does not "hear" from the other after a certain time, the assumption is that the communication link is lost and the radio "gives up" trying to communicate. If we set the time out to low, the system gives up trying to communicate too soon. If we set it to high, it will "waste time" trying to communicate when there is a problem. This is important with we need to collect data from several data collection stations and can't keep waiting because of a bad radio com issue.

The closest most people get to this is when their smart phone is trying to connect to wifi and can't make a connection. It will give up trying after some time. The next closest is when trying to fax to a non-fax number and the fax machine tries a few times and then gives up when it doesn't get an answer or "handshake" from the other end.

I put this out there to say that maybe some network speeds are too slow for Arc Map to work with when doing the heavy data processing and some processes in Arc Map give up when the other end of the network doesn't answer soon enough due to bottle necked data transfer.

I have already asked about this issue with another set of data before, but I am stuck on DEM Reconditioning again with HRESULT E_FAIL error (returned frmoa call to a COM component)

I have tried everything i could find on this on the forum. I have deleted and created the layers over and over again for the past 2 days. I am all out of ideas. I have used my DEM, my NHD layer and zoomed extent and used the display extent for my "Environment Extend". My background processing is off. My Temp Folder is empty and results are removed. I also set my target locations to a folder (that i made for the project) for raster data and a gdb with the same name (under the raster folder) for the vector data.

I also set the target location for all three of the following: Ap UtilitiesConfig, DefaultConfig and HydroConfig.

Is there anything I am missing?

The name of my msx is short with no number or space too. Same with the name of my folder and gdb.

Layla - Have you tried moving your data and project to your local PC hard drive? I don't see that in that on your list of things you've tried. Make sure your folder path is short and simple with no spaces (I used C:\GIS\MoragaPt25 for my last one). Put the agreestream layer in a geodataset. I found that seems to work best. Start a new mxd and add base layers to is. Mine are rawdem, agreestream, innerwalls, outerwalls (only use outerwalls once in a while). By starting a new mxd, the target locations get set automatically. Let us know if you done this, and if not, if when you do it, if it helps.

Thank you for your quick reply. I actually had done that too. Still no luck.

By agreestream layer, you mean the NHLFlowline (USGS)/the stream layer I will use on my DEM layer in AgreeDEM? IF yes, I have that in a GeoDataBase (.gdb) as well. I am trying it with arcGIS 10.1 now (I was using 10.2) I will let you know how it goes.

Glad it is working! I have my agreestream layer in a gdb. I've been using 10.1. We haven't "upgraded" to 10.2 yet.

I stopped changing the layer names in the tools a while back and started just using the layer names the same as the Arc Hydro defaults. So, I use "rawdem", "agreestream", "innerwalls", etc. Succumming to the defaults saves time for me because each project actually references the same agreestream and walls layers. I work in and for the county and so it make sense to build on this layer over time. If I have adjacent watersheds of datasets to bring into the agreestream layer, I don't have to clip them. I believe the processing extents limits where the tools "look" and it doesn't add much to the processing time. At least I don't have to take the time to clip them for every project.

When I move the data to the C:drive, this actually only has to include the rawdem and the mxd. My agreestream and walls layers are actually left in a gdb on the server. The creation/read/write of the rasters that precipitate from the process are the ones that I believe are better to have (or have created) on the local drive to eliminate the HRESULT E_FAILerror.

The agree stream layer I use is the storm drain layer that helps define the flow pattern in flat urbanized areas. It also includes “streams” I use to cut through rural road embankments and freeway embankments where there are culverts.

I encountered the same error (a shorter message, but same HRESULT E_FAIL error) when I wanted to create catchment polygons from my catchments. (input: cat, output:Catchment)

and I tried my data with another computer that had ArcGIS 10.1 and it worked without a hassle! (I was working with 10.2 when it didn't work)

Just wanted to put this out here.

Also , i have a question regarding AgreeDEM. Although, I have been doing AgreeDEM for my data, I havent really understood how to figure out Smooth and Sharp drop/raise. When I am given a set of data, how do I figure that out? I usually use 2,3 or 5 for my buffer cell size; but for smooth and sharp drop/raise, I am not sure what to do. I use 0.5-1 for smooth and 5-10 for sharp, and my reasons are that I am working in Florida region, and it is a flat terrain. I am not sure if I am using the right factors.

I know that it is said, I can do trial and error and see the results and change the factors, but since there are 3 different factors, it will take a lot of trails to really understand the effect of each factor.

thanks for the links, I had the 10.2 version of ArcHydro installed already. I am still having issues although I was using 10.1 and I did manage to get polygon catchments. I get the same HRESULT E_Fail error at Drainage Line Processing.

The Arc Hydro help explains the three input. Here's my interpretation and practice (bullet items):

Stream buffer (cells) – this is the number of cells around the linear feature class for which the smoothing will occur.

I've found that the narrower this is, the less it disrupts what the rawdem "tells you" about the surface. I usually use 2 and I work with a 10' DEM. I believe you can use 1 and still have it work.

Smooth drop/raise – this is the amount (in vertical units) that the river will be dropped (if the number is positive) or the fence extruded (if the number is negative). This value will be used to interpolate DEM into the buffered area (between the boundary of the buffer and the dropped/raised vector feature).

If you don't want to wipe out levees around your stream, then keep this low.

If after you look at your flow direction (fdr) grid and you find that the fdr creates parallel streams where there should be only one, then increase this. I understand (I think correctly) that this basically smooths out the banks of your burned in stream so that any parallel streams or any pockets that should flow directly to the stream, but wouldn't otherwise, are eliminated.

You can use the flow path tracing tool in the Arc Hydro toolbar to investigate. If you get parallel streams, you will want more smooth drop.

So, to see what smooth drop/raise you need. Start with zero and just go to the flow direction grid in the processing and stop. Then see if you have any flow direction issues right along the streams that you don't want, increase it.

Sharp drop/raise – this is the additional amount (in vertical units) that the river will be dropped (if the number is positive) or the fence extruded (if the number is negative). This has the effect of additional burning/fencing on top of the smooth buffer interpolation. It needs to be performed to ensure preserving the linear features used for burning/fencing.

This value can be very large (10,000 would even work). Where the agreestream polylines are, the burning process lowers those cells this depth.

I've never used this to extrude a "fence". I use innerwalls for that.

Since the ultimate goal is to get a good flow direction grid (fdr), the final elevations of the agreedem or walleddem (if you build walls too) are not that important. All of the rest of the processing is dependant on the fdr. If you need an elevation later you will take that from the rawdem.

I don't find the GeoNet forum that easy to use. I'm going to try out Geographic Information Systems Stack Exchange and see if it is a good replacement. I'll still look here from time to time. If GeoStacker works better, I may abandon this format. Just not that good of a format for a forum. Go to this discussion to see what others think.

Some who follow Arc Hydro or this thread might have info on bathymetry, but you'll have a better chances of finding an answer if you go to the main GeoNet page and search bathymetry. You might find a broader audience for your question there. This thread is specific to ArcHydro and does not specifically cover data sources.

Mark: First of all I apologize for re-posting my query from another forum thread. I get the following error (see attached). I have made sure the target locations are set correctly as you have described. My files are on local drive, and I have also gone through most of the useful suggestions you have provided in this post, but with no success.

Seriously, this is one of those "generic" error messages. I seems like you are doing things that reduce this error: local drive, target locations, etc. Make sure you have the Spatial Analyst extension turned on and make sure the layers are all in the same coordinate system.

Even recently I had some problems with the catchment polygon processing (raster to polygon). It took a PC reboot to "fix" it. I'm at a loss to understand the cause. It has been working fine lately.

The Arc Hydro processing is doing a lot. Sometimes I sense that I get an error if it has been a while since I saved or closed and restarted ArcMap. I have never heard anyone talk about this, but I wonder if the "undo" list gets too long for ArcMap to keep track of when doing all the geoprocessing and that causes a memory or other problem.

I will soon be getting v10.2.2 and so I'll be able to experience upgrade errors then. Maybe its a version issue.

I just got 10.2.2 installed on a laptop and am testing the new version of Arc Hydro. All worked well until I got to fill sinks. After restarting ArcMap, etc., I reset the processing extents to be that of the rawdem I'm using: an area a little bigger than my study extents. All worked smoothly after that!

So, somewhere in the process, Arc Hydro might change or set the processing extents and if all does not work just right, it doesn't get changed back and that causes problems. If you have problems, see if that fixes it.

It would be nice if Arc Map had a way to show me what the processing extents are or had a way in Model builder to have a layer (like rawdem) be used to set the processing extents for the mxd. Those features would be really nice.

I have similar problems, as you mentioned, with DEM Fill. In fact, I am having all these problems while working on the tutorial data as prescribed by ArcHydro itself so I assume the fault is not in the data. I use Windows 8.1 and ArcMap 10.2.2. I do get a feeling that the error may be due to incorrect target location, which I am unable to locate as it is not mentioned clearly for Win 8.1 ( There is no C:/Users/Temp...). Also, I don't understand what " donot store a raster in a geodatabase" means. Can you please help me with this. I get the same error message as Mr. Mallya has with his problems in DEM Reconditioning.

I am currently performing a hydrologic analysis of a filled 5m raster DEM (dendritic). I have already been able to perform pre-processing via the basic dendritic terrain workflow in GP tools. However I am now trying to perform the Hydro Network generation. I am getting an error message shortly after executing the command. I have tried things mentioned including deleting the folders and geodatabases and starting again, setting geoprocessing extents, clearing temporary files. However I have not been successful. I will keep trying things but just wondering if you had any ideas on how to get around this?

This is a very common error that could mean a number of things (not that I know what they are!). I did a little search and found a thread on the error. c# - What is a NullReferenceException and how do I fix it? - Stack OverflowI guess "Object Reference Not Set to an Object" can also be called "Null Reference Exception". Subheadings at the link above seem to make more sense than the techno-talk in the post. It looks like the error comes up when the program runs across a "Null" value in a variable. Make sure the features have values in key fields.

Naming conventions is one that I've found is important. In the screen capture you posted it looks like you are using default names and they don't have any spaces. Sometimes the name length can cause problems. You could try creating a project directory that is not as "deep". I use C:/GIS/<Project> for my work. I save the mxd with relative paths and then move the project to a server that is backed up later.

I'm stumped and wondering if someone can help explain something. I'm using ArcHydro to do some analysis where there are known sinks, and trying to use the Flow Direction with Sinks tool. In the resulting Fdr grid, I'm used to seeing only the D8 directions (1,2,4,8,16,etc.), but i'm now seeing around 60 different numbers in the VALUE field ranging from 1 to 255. The non-D8 values do not have a high cell COUNT relative to the D8 but they are not insignificant. Is this correct and should I continue with my analysis, or is there something wrong here?

Thanks for your extremely useful thread on troubleshooting ARCHYDRO. I've implemented your suggestions and I'm still getting the same error when I attempt to run the depression evaluation tool. I'm attempting to run this tool on a 1m LIDAR DEM about 650 mb in size, that has already been prescreened for small sinks. The tool will run up to the drainage area calculation step and then crash with the following message:

What format is the input raster? Make sure it's an esri GRID format, and make sure it's saved in a folder, not a geodatabase. Also make sure than none of your outputs are set to intermediate, if you're using a model.

I've been having an issue with ArcHydro models for some time now, and finally have some time to look into it. The model i'm working with gives me what I want, but it keeps deleting some of the output after it runs, or after the mxd is saved and reopened. This happens to only a few of the outputs, but happens every time usually to the same ones, which are both raster and vector. They are behaving as though they are set to Intermediate, but that is definitely not the case and I also make sure to add them to the display and save the mxd. Fortunately, this does not happen to the ultimate outputs which I need, like fdr (flowdirection) but it makes it very difficult and frustrating to go back and troubleshoot or tweak the model since I lose several steps along the way. I don't have the time to go piece by piece, running the model, and figuring out what happens at every step along the way, so I'm hoping someone has encountered this before or has any thoughts. Below is a screen shot of the model, with the steps numbered in order. The outputs which have a tendency to vanish after the model completes are PreFillDEM, SinkPoly, and fil...where do they go and why?!?

My practice is to create a tool box and put several models in it. I start the names of the models with numbers so I can keep the order straight. The models may have a dozen steps or just a couple. This is how I've kept one crash from a big model from requiring a whole new start.

I also will sometimes if errors are persistent, I close the mxd and delete all the output (gdbs and all). I keep any of the main inputs. Then I reboot. This is sometimes the only thing that gets me past an error. Never know why this is, but it works.

I want to use a shapefile I have for a lake as the only sink in a deranged basin, but the Create Sink Structures routine will not accept the shapefile. Is this because it expects to find HydroIDs in the attribute table?

I seem to be digging myself into a deeper hole. Can't finish an archydro project due to the tools throwing errors or ArcMap crashing. I keep starting clean projects in new directories, following your advice, hoping something will magically get resolved, but now merely attempting to set default locations causes ArcMap to crash. Installed 10.4.With last project I got all the way through defining the catchment grid but it exited with error at the polygon processing step. I've cleared my temp folder, have lots of RAM and diskspace. I've successfully been creating catchments for years.

the maddening thing is that when ArcHydro crashes map there is (apparently) no log to diagnose what went wrong. I'm getting the impression it has something to do with writing or modifying the files that it creates. For example, I can get through the processing step all the way to creating the catchment polygons. The processing takes several minutes, then ArcMap crashes ("encounters a serious error"). However, the "catchment" feature layer is in fact created, but it's attribute table doesn't have HydroIDs in it. No amount of coaxing will get hydrotools to execute past this step.

p.s. I was running on an HP desktop, 8 cores, 32 GB RAM. Thinking the problems were somehow tied to my installation, I began running ArcGIS 10.4 on a Parallels VM on my macbook. Exact same behavior - continual crashes. Makes me think the problem began with recent versions. I was running hydrotools under 10.1 and 10.2 with no problems

Hi Siri, I am having the exact same problem. I have been using ArcHydro for years, and am usually able to troubleshoot problems that come up, but this one has me stumped. Just last week I performed some ArcHydro basin analyses that went smoothly. The day before yesterday, the IT folks installed ArcGIS 10.4 on my machine. I then downloaded and installed ArcHydro tools for 10.4, and everything went fine up to creation of catchment polygons. Complete ArcMap crash. A catchment feature class was created, but like with your experience, the HydroID field is all "Null". I started again from scratch and had the same result.

The basins I am working on are generally small. Prior to 10.4, most ArcHydro operations were taking no more than a couple minutes. If you've found some solution to this I'd appreciate hearing about it.

On the main Arc Hydro Tools toolbar, under the Attribute Tools dropdown, is a "Add Hydro ID" tool. I tried using it to populate the HydroID field in the catchment polygon layer. Instant ArcMap crash, with the unhelpful and unapologetic "Send ESRI an Error Report" dialogue box.

Thanks, Mark. The community is grateful for the service you provide. BTW, I am processing large basins (Ganges, Indus, Brahmaputra, Amu Darya, Syr Darya, separately, using a 90m DEM) so I wonder whether I'm running into issues with the attribute tables being too large. I don't recall running into problems when I process small basins.

My projects are not so large. I don't know if the large size of the tables causes problems. I have heard, and do practice normally, putting data in geodatabases to reduce the instability issues that can come when using simple shape files.

My most recent discovery is more generally related to geoprocessing and is not specific to Arc Hydro. However, since Arc Hydro is heavy on geoprocessing, I wanted to post this here.

My latest Arc Hydro project had ArcMap freezing up when saving and at other times. I'd have to wait forever or, out of impatient frustration, I would "X" out and/or cancel it using Task Manager. Then I heard about something in the geoprocessing options that seems to have put and end to that!

I have a problem when calculating the Longest Flowpath using HEC-GeoHMS.It turns out that the program starts to compile, stays for more than 20 minutes calculating, after that the program is closed, I open it again and all the progress of the Longest flowpath calculation is lost.

I have tried deleting the temporary files, changing the location of the files and everything said above.I need if someone can help me with this problem please.Thanks